Defective element disabling circuit having a laser-blown fuse

摘要

A decoder circuit for disabling a defective element in a circuit having redundant replacement elements employs a fuse on a signal path through the decoder circuit from a selection device to a low-impedance output device and a weak default circuit, such as a pull-up transistor, for forcing the state of the output circuit to a low-impedance default state when the fuse is blown.